The laid-open application DE 198 27 360 A1 discloses a medical instrument with an elongate shaft which, at the distal end, has a spatula tip, and in the proximal area of which a laterally projecting handle is arranged. The handle is connected to the shaft in such a way that an outer face of the instrument directed away from the handle has a substantially uniform surface extending continuously from the distal to the proximal end. The known instrument also has an endoscope lens system with an eyepiece inclined, substantially on the same side as the handle, in relation to a longitudinal central axis of the shaft. The known medical instrument is intended for endoscopic removal of the vena saphena magna, wherein the instrument is inserted through an incision in the knee area and is advanced along the vein as far as the inguinal region or the ankle region almost parallel to the skin surface. The endoscopic intervention with visual monitoring permits removal of the vena saphena magna in a way that is particularly gentle on tissue, and only a single, relatively short scar is left behind.
Endoscopic methods are also known in thyroid surgery. In the technique known as EndoCATS (endoscopic cephalic access thyroid surgery), an incision is made in the area of the scalp covered by hair behind the ear. A retractor spatula is advanced through natural spaces into the thyroid bed (spatium de Quervain). After the operation, the incision is covered by regrowth of hair on the head, such that the scar remains hidden from view. In order to guide the spatula through the natural spaces to the actual operating site, the spatula is rotated about the longitudinal axis of the instrument depending on the position and direction of the usable spaces during the advance movement. However, since the proximal end area of the instrument lies closely on the scalp, the handling of the instrument in order to perform such a rotation movement is made difficult and, in particular, the available angle range is relatively narrow.